{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T06:05:08Z","timestamp":1790661908061,"version":"4.1.0"},"reference-count":18,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T00:00:00Z","timestamp":1790640000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Cell Dev. Biol."],"abstract":"<jats:p>\n                    Autophagy-related protein 8 (ATG8) family proteins are ubiquitin-like modifiers that undergo ATG4-mediated processing before lipid conjugation. However, the structural and functional diversification of insect ATG8 proteins remains poorly understood. Here, comparative sequence analysis identified a 248-amino-acid LC3C-related protein from the silkworm\n                    <jats:italic>Bombyx mori<\/jats:italic>\n                    (BmLC3) containing two tandem LC3-like regions separated by an internal glycine at position 135 (G135), in addition to the canonical C-terminal glycine at position 248 (G248). In HeLa cells, N-terminally GFP-tagged BmLC3 generated a lower-molecular-weight product, whereas substitution of G135 with alanine prevented its formation. BmLC3 processing was markedly reduced in ATG4B-knockout cells and restored by expression of\n                    <jats:italic>B. mori<\/jats:italic>\n                    ATG4B (BmATG4B), demonstrating ATG4B-dependent cleavage at the internal junction. An isolated GFP-tagged C-terminal BmLC3 region showed increased punctate localization following starvation and bafilomycin A1 treatment, while BmATG4B also processed membrane-tethered mammalian ATG8 reporters in a cell-based cleavage assay. In a tandem fluorescent BmLC3 reporter, cleavage generated a C-terminal product beginning with Tyr136 that showed little mRFP signal, whereas Y136M increased both mRFP fluorescence and the mRFP\/GFP band-intensity ratio. Together, these findings reveal a previously unrecognized mode of ATG8 diversification and support a model in which internal proteolysis couples fragment generation to N-terminal residue-dependent control of C-terminal product stability.\n                  <\/jats:p>","DOI":"10.3389\/fcell.2026.1957836","type":"journal-article","created":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T05:47:58Z","timestamp":1790660878000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["ATG4B-dependent processing of tandem-domain BmLC3 exposes a Tyr136-regulated C-terminal fragment"],"prefix":"10.3389","volume":"14","author":[{"given":"Won-Dong","family":"Shin","sequence":"first","affiliation":[{"name":"Research Institute of Invertebrate Vector, Kyungpook National University","place":["Sangju, Republic of Korea"]},{"name":"Department of Vector Entomology, College of Ecology and Environment, Kyungpook National University","place":["Sangju, Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hun-Joo","family":"Kim","sequence":"additional","affiliation":[{"name":"Research Institute of Invertebrate Vector, Kyungpook National University","place":["Sangju, Republic of Korea"]},{"name":"Department of Ecological Science, College of Ecology and Environment, Kyungpook National University","place":["Sangju, Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sang-Hee","family":"Ma","sequence":"additional","affiliation":[{"name":"Department of Ecological Science, College of Ecology and Environment, Kyungpook National University","place":["Sangju, Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sang-Won","family":"Park","sequence":"additional","affiliation":[{"name":"Research Institute of Invertebrate Vector, Kyungpook National University","place":["Sangju, Republic of Korea"]},{"name":"Department of Vector Entomology, College of Ecology and Environment, Kyungpook National University","place":["Sangju, Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yong-Woo","family":"Jun","sequence":"additional","affiliation":[{"name":"Department of Ecological Science, College of Ecology and Environment, Kyungpook National University","place":["Sangju, Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Do-Kyung","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Biological Sciences and Biotechnology, College of Life Sciences and Nanotechnology, Hannam University","place":["Daejeon, Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"In-Young","family":"Hwang","sequence":"additional","affiliation":[{"name":"Center for Cognition and Sociality, Institute for Basic Science (IBS)","place":["Daejeon, Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Deok-Jin","family":"Jang","sequence":"additional","affiliation":[{"name":"Research Institute of Invertebrate Vector, Kyungpook National University","place":["Sangju, Republic of Korea"]},{"name":"Department of Vector Entomology, College of Ecology and Environment, Kyungpook National University","place":["Sangju, Republic of Korea"]},{"name":"Department of Ecological Science, College of Ecology and Environment, Kyungpook National University","place":["Sangju, Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jin-A","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Biological Sciences and Biotechnology, College of Life Sciences and Nanotechnology, Hannam University","place":["Daejeon, Republic of Korea"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,9,29]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"976","DOI":"10.1080\/15548627.2019.1569925","article-title":"Redundancy of human ATG4 protease isoforms in autophagy and LC3\/GABARAP processing revealed in cells","volume":"15","author":"Agrotis","year":"2019","journal-title":"Autophagy"},{"key":"B2","doi-asserted-by":"publisher","first-page":"466","DOI":"10.3389\/fcell.2020.00466","article-title":"Multiple functions of ATG8 family proteins in plant autophagy","volume":"8","author":"Bu","year":"2020","journal-title":"Front. 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